(2R,4S,5R,6R)-5-acetamido-2-[(2R,3S,4R,5S)-5-acetamido-4-[(2R,3R,4S,5S,6R)-6-[[(2R,3R,4R,5S,6R)-3-acetamido-5-[(2S,3R,4R,5R,6R)-3,4-dihydroxy-6-(hydroxymethyl)-5-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-6-(hydroxymethyl)-4-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxymethyl]-4-[(2S,3R,4S,5R,6R)-4,5-dihydroxy-6-(hydroxymethyl)-3-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-5-hydroxy-3-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-2,3,6-trihydroxyhexoxy]-4-hydroxy-6-[(1R,2R)-1,2,3-trihydroxypropyl]oxane-2-carboxylic acid

C69H117N3O50 — CID 91847125

About (2R,4S,5R,6R)-5-acetamido-2-[(2R,3S,4R,5S)-5-acetamido-4-[(2R,3R,4S,5S,6R)-6-[[(2R,3R,4R,5S,6R)-3-acetamido-5-[(2S,3R,4R,5R,6R)-3,4-dihydroxy-6-(hydroxymethyl)-5-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-6-(hydroxymethyl)-4-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxymethyl]-4-[(2S,3R,4S,5R,6R)-4,5-dihydroxy-6-(hydroxymethyl)-3-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-5-hydroxy-3-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-2,3,6-trihydroxyhexoxy]-4-hydroxy-6-[(1R,2R)-1,2,3-trihydroxypropyl]oxane-2-carboxylic acid

(2R,4S,5R,6R)-5-acetamido-2-[(2R,3S,4R,5S)-5-acetamido-4-[(2R,3R,4S,5S,6R)-6-[[(2R,3R,4R,5S,6R)-3-acetamido-5-[(2S,3R,4R,5R,6R)-3,4-dihydroxy-6-(hydroxymethyl)-5-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-6-(hydroxymethyl)-4-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxymethyl]-4-[(2S,3R,4S,5R,6R)-4,5-dihydroxy-6-(hydroxymethyl)-3-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-5-hydroxy-3-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-2,3,6-trihydroxyhexoxy]-4-hydroxy-6-[(1R,2R)-1,2,3-trihydroxypropyl]oxane-2-carboxylic acid (PubChem CID 91847125) has the molecular formula C69H117N3O50 and a molecular weight of 1788.67 g/mol. Its IUPAC name is (2R,4S,5R,6R)-5-acetamido-2-[(2R,3S,4R,5S)-5-acetamido-4-[(2R,3R,4S,5S,6R)-6-[[(2R,3R,4R,5S,6R)-3-acetamido-5-[(2S,3R,4R,5R,6R)-3,4-dihydroxy-6-(hydroxymethyl)-5-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-6-(hydroxymethyl)-4-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxymethyl]-4-[(2S,3R,4S,5R,6R)-4,5-dihydroxy-6-(hydroxymethyl)-3-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-5-hydroxy-3-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-2,3,6-trihydroxyhexoxy]-4-hydroxy-6-[(1R,2R)-1,2,3-trihydroxypropyl]oxane-2-carboxylic acid.

Molecular Properties

• Compound Name: (2R,4S,5R,6R)-5-acetamido-2-[(2R,3S,4R,5S)-5-acetamido-4-[(2R,3R,4S,5S,6R)-6-[[(2R,3R,4R,5S,6R)-3-acetamido-5-[(2S,3R,4R,5R,6R)-3,4-dihydroxy-6-(hydroxymethyl)-5-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-6-(hydroxymethyl)-4-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxymethyl]-4-[(2S,3R,4S,5R,6R)-4,5-dihydroxy-6-(hydroxymethyl)-3-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-5-hydroxy-3-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-2,3,6-trihydroxyhexoxy]-4-hydroxy-6-[(1R,2R)-1,2,3-trihydroxypropyl]oxane-2-carboxylic acid
• PubChem CID: 91847125
• Molecular Formula: C69H117N3O50
• Molecular Weight: 1788.67 g/mol
• Exact Mass: 1787.67
• IUPAC Name: (2R,4S,5R,6R)-5-acetamido-2-[(2R,3S,4R,5S)-5-acetamido-4-[(2R,3R,4S,5S,6R)-6-[[(2R,3R,4R,5S,6R)-3-acetamido-5-[(2S,3R,4R,5R,6R)-3,4-dihydroxy-6-(hydroxymethyl)-5-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-6-(hydroxymethyl)-4-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxymethyl]-4-[(2S,3R,4S,5R,6R)-4,5-dihydroxy-6-(hydroxymethyl)-3-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-5-hydroxy-3-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-2,3,6-trihydroxyhexoxy]-4-hydroxy-6-[(1R,2R)-1,2,3-trihydroxypropyl]oxane-2-carboxylic acid
• SMILES: CC(=O)N[C@H]1[C@H](OC[C@H]2O[C@@H](O[C@@H]([C@@H](O)[C@H](O)CO[C@]3(C(=O)O)C[C@H](O)[C@@H](NC(C)=O)[C@H]([C@H](O)[C@H](O)CO)O3)[C@H](CO)NC(C)=O)[C@H](O[C@H]3O[C@H](C)[C@H](O)[C@H](O)[C@H]3O)[C@@H](O[C@@H]3O[C@H](CO)[C@H](O)[C@H](O)[C@H]3O[C@H]3O[C@H](C)[C@H](O)[C@H](O)[C@H]3O)[C@H]2O)O[C@H](CO)[C@@H](O[C@@H]2O[C@H](CO)[C@H](O[C@H]3O[C@H](C)[C@H](O)[C@H](O)[C@H]3O)[C@H](O)[C@H]2O)[C@@H]1O[C@H]1O[C@H](C)[C@H](O)[C@H](O)[C@H]1O
• InChI: InChI=1S/C69H117N3O50/c1-16-33(84)41(92)47(98)61(107-16)116-53-28(12-76)113-65(51(102)46(53)97)117-54-29(13-77)112-60(32(72-22(7)80)56(54)118-62-48(99)42(93)34(85)17(2)108-62)105-15-30-40(91)57(119-66-58(45(96)39(90)27(11-75)111-66)120-63-49(100)43(94)35(86)18(3)109-63)59(121-64-50(101)44(95)36(87)19(4)110-64)67(114-30)115-52(23(9-73)70-20(5)78)38(89)26(83)14-106-69(68(103)104)8-24(81)31(71-21(6)79)55(122-69)37(88)25(82)10-74/h16-19,23-67,73-77,81-102H,8-15H2,1-7H3,(H,70,78)(H,71,79)(H,72,80)(H,103,104)/t16-,17-,18-,19-,23+,24+,25-,26-,27-,28-,29-,30-,31-,32-,33+,34+,35+,36+,37-,38+,39+,40+,41+,42+,43+,44+,45+,46-,47-,48-,49-,50-,51-,52-,53+,54-,55-,56-,57+,58-,59-,60-,61-,62-,63-,64-,65+,66+,67+,69-/m1/s1
• InChIKey: UYWKFBVYWSFKLE-RJKCBCMVSA-N
• XLogP: -19.42
• TPSA: 836.95 Ų
• H-Bond Donors: 31
• H-Bond Acceptors: 49
• Rotatable Bonds: 34
• Heavy Atoms: 122
• Complexity: —

Lipinski Rule of Five

3 violations

Rule	Value
MW ≤ 500	1788.67
LogP ≤ 5	-19.42
H-Bond Donors ≤ 5	31
H-Bond Acceptors ≤ 10	49

Frequently Asked Questions

What is the IUPAC name of (2R,4S,5R,6R)-5-acetamido-2-[(2R,3S,4R,5S)-5-acetamido-4-[(2R,3R,4S,5S,6R)-6-[[(2R,3R,4R,5S,6R)-3-acetamido-5-[(2S,3R,4R,5R,6R)-3,4-dihydroxy-6-(hydroxymethyl)-5-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-6-(hydroxymethyl)-4-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxymethyl]-4-[(2S,3R,4S,5R,6R)-4,5-dihydroxy-6-(hydroxymethyl)-3-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-5-hydroxy-3-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-2,3,6-trihydroxyhexoxy]-4-hydroxy-6-[(1R,2R)-1,2,3-trihydroxypropyl]oxane-2-carboxylic acid?

The IUPAC name of (2R,4S,5R,6R)-5-acetamido-2-[(2R,3S,4R,5S)-5-acetamido-4-[(2R,3R,4S,5S,6R)-6-[[(2R,3R,4R,5S,6R)-3-acetamido-5-[(2S,3R,4R,5R,6R)-3,4-dihydroxy-6-(hydroxymethyl)-5-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-6-(hydroxymethyl)-4-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxymethyl]-4-[(2S,3R,4S,5R,6R)-4,5-dihydroxy-6-(hydroxymethyl)-3-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-5-hydroxy-3-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-2,3,6-trihydroxyhexoxy]-4-hydroxy-6-[(1R,2R)-1,2,3-trihydroxypropyl]oxane-2-carboxylic acid (CID 91847125) is (2R,4S,5R,6R)-5-acetamido-2-[(2R,3S,4R,5S)-5-acetamido-4-[(2R,3R,4S,5S,6R)-6-[[(2R,3R,4R,5S,6R)-3-acetamido-5-[(2S,3R,4R,5R,6R)-3,4-dihydroxy-6-(hydroxymethyl)-5-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-6-(hydroxymethyl)-4-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxymethyl]-4-[(2S,3R,4S,5R,6R)-4,5-dihydroxy-6-(hydroxymethyl)-3-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-5-hydroxy-3-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-2,3,6-trihydroxyhexoxy]-4-hydroxy-6-[(1R,2R)-1,2,3-trihydroxypropyl]oxane-2-carboxylic acid.

What is the SMILES notation for (2R,4S,5R,6R)-5-acetamido-2-[(2R,3S,4R,5S)-5-acetamido-4-[(2R,3R,4S,5S,6R)-6-[[(2R,3R,4R,5S,6R)-3-acetamido-5-[(2S,3R,4R,5R,6R)-3,4-dihydroxy-6-(hydroxymethyl)-5-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-6-(hydroxymethyl)-4-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxymethyl]-4-[(2S,3R,4S,5R,6R)-4,5-dihydroxy-6-(hydroxymethyl)-3-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-5-hydroxy-3-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-2,3,6-trihydroxyhexoxy]-4-hydroxy-6-[(1R,2R)-1,2,3-trihydroxypropyl]oxane-2-carboxylic acid?

The canonical SMILES for (2R,4S,5R,6R)-5-acetamido-2-[(2R,3S,4R,5S)-5-acetamido-4-[(2R,3R,4S,5S,6R)-6-[[(2R,3R,4R,5S,6R)-3-acetamido-5-[(2S,3R,4R,5R,6R)-3,4-dihydroxy-6-(hydroxymethyl)-5-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-6-(hydroxymethyl)-4-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxymethyl]-4-[(2S,3R,4S,5R,6R)-4,5-dihydroxy-6-(hydroxymethyl)-3-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-5-hydroxy-3-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-2,3,6-trihydroxyhexoxy]-4-hydroxy-6-[(1R,2R)-1,2,3-trihydroxypropyl]oxane-2-carboxylic acid is CC(=O)N[C@H]1[C@H](OC[C@H]2O[C@@H](O[C@@H]([C@@H](O)[C@H](O)CO[C@]3(C(=O)O)C[C@H](O)[C@@H](NC(C)=O)[C@H]([C@H](O)[C@H](O)CO)O3)[C@H](CO)NC(C)=O)[C@H](O[C@H]3O[C@H](C)[C@H](O)[C@H](O)[C@H]3O)[C@@H](O[C@@H]3O[C@H](CO)[C@H](O)[C@H](O)[C@H]3O[C@H]3O[C@H](C)[C@H](O)[C@H](O)[C@H]3O)[C@H]2O)O[C@H](CO)[C@@H](O[C@@H]2O[C@H](CO)[C@H](O[C@H]3O[C@H](C)[C@H](O)[C@H](O)[C@H]3O)[C@H](O)[C@H]2O)[C@@H]1O[C@H]1O[C@H](C)[C@H](O)[C@H](O)[C@H]1O.

What is the InChIKey of (2R,4S,5R,6R)-5-acetamido-2-[(2R,3S,4R,5S)-5-acetamido-4-[(2R,3R,4S,5S,6R)-6-[[(2R,3R,4R,5S,6R)-3-acetamido-5-[(2S,3R,4R,5R,6R)-3,4-dihydroxy-6-(hydroxymethyl)-5-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-6-(hydroxymethyl)-4-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxymethyl]-4-[(2S,3R,4S,5R,6R)-4,5-dihydroxy-6-(hydroxymethyl)-3-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-5-hydroxy-3-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-2,3,6-trihydroxyhexoxy]-4-hydroxy-6-[(1R,2R)-1,2,3-trihydroxypropyl]oxane-2-carboxylic acid?

The InChIKey is UYWKFBVYWSFKLE-RJKCBCMVSA-N. The full InChI is InChI=1S/C69H117N3O50/c1-16-33(84)41(92)47(98)61(107-16)116-53-28(12-76)113-65(51(102)46(53)97)117-54-29(13-77)112-60(32(72-22(7)80)56(54)118-62-48(99)42(93)34(85)17(2)108-62)105-15-30-40(91)57(119-66-58(45(96)39(90)27(11-75)111-66)120-63-49(100)43(94)35(86)18(3)109-63)59(121-64-50(101)44(95)36(87)19(4)110-64)67(114-30)115-52(23(9-73)70-20(5)78)38(89)26(83)14-106-69(68(103)104)8-24(81)31(71-21(6)79)55(122-69)37(88)25(82)10-74/h16-19,23-67,73-77,81-102H,8-15H2,1-7H3,(H,70,78)(H,71,79)(H,72,80)(H,103,104)/t16-,17-,18-,19-,23+,24+,25-,26-,27-,28-,29-,30-,31-,32-,33+,34+,35+,36+,37-,38+,39+,40+,41+,42+,43+,44+,45+,46-,47-,48-,49-,50-,51-,52-,53+,54-,55-,56-,57+,58-,59-,60-,61-,62-,63-,64-,65+,66+,67+,69-/m1/s1.

What are the key properties of (2R,4S,5R,6R)-5-acetamido-2-[(2R,3S,4R,5S)-5-acetamido-4-[(2R,3R,4S,5S,6R)-6-[[(2R,3R,4R,5S,6R)-3-acetamido-5-[(2S,3R,4R,5R,6R)-3,4-dihydroxy-6-(hydroxymethyl)-5-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-6-(hydroxymethyl)-4-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxymethyl]-4-[(2S,3R,4S,5R,6R)-4,5-dihydroxy-6-(hydroxymethyl)-3-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-5-hydroxy-3-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-2,3,6-trihydroxyhexoxy]-4-hydroxy-6-[(1R,2R)-1,2,3-trihydroxypropyl]oxane-2-carboxylic acid?

(2R,4S,5R,6R)-5-acetamido-2-[(2R,3S,4R,5S)-5-acetamido-4-[(2R,3R,4S,5S,6R)-6-[[(2R,3R,4R,5S,6R)-3-acetamido-5-[(2S,3R,4R,5R,6R)-3,4-dihydroxy-6-(hydroxymethyl)-5-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-6-(hydroxymethyl)-4-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxymethyl]-4-[(2S,3R,4S,5R,6R)-4,5-dihydroxy-6-(hydroxymethyl)-3-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-5-hydroxy-3-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-2,3,6-trihydroxyhexoxy]-4-hydroxy-6-[(1R,2R)-1,2,3-trihydroxypropyl]oxane-2-carboxylic acid has a molecular weight of 1788.67 g/mol, XLogP of -19.42, 34 rotatable bonds, 31 hydrogen bond donors, and 49 hydrogen bond acceptors.

Where does this data come from?

All data for (2R,4S,5R,6R)-5-acetamido-2-[(2R,3S,4R,5S)-5-acetamido-4-[(2R,3R,4S,5S,6R)-6-[[(2R,3R,4R,5S,6R)-3-acetamido-5-[(2S,3R,4R,5R,6R)-3,4-dihydroxy-6-(hydroxymethyl)-5-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-6-(hydroxymethyl)-4-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxymethyl]-4-[(2S,3R,4S,5R,6R)-4,5-dihydroxy-6-(hydroxymethyl)-3-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-5-hydroxy-3-[(2R,3R,4S,5R,6R)-3,4,5-trihydroxy-6-methyloxan-2-yl]oxyoxan-2-yl]oxy-2,3,6-trihydroxyhexoxy]-4-hydroxy-6-[(1R,2R)-1,2,3-trihydroxypropyl]oxane-2-carboxylic acid is sourced from PubChem (CID 91847125), the world's largest open chemistry database maintained by the National Library of Medicine (NIH).